With virtualization so popular, gone are the days when you would need to partition your hard drive and configure dual-boot to give you the option of running more than one OS on your computer.

Sun VirtualBox is a free, open source x86 virtualization software which allows you to create virtual machines (VMs) on your computer’s Operating System (host OS) and run other Operating Systems (guest OS) within the VMs. Sun VirtualBox is easy and intuitive to use and will enable you to quickly test an OS. Well, many OSes nowadays come with LIVE CDs/DVDs to enable you have a test run, but running these OSes in a virtualization software like Sun VirtualBox works better and faster.

Given below is a screenshot of my Sun VirtualBox console. As you can see, I use Sun VirtualBox to run three 64-bit guest OSes (Fedora 11, Solaris 10, Ubuntu 9.04). I have run 2 guest OSes simultaneously, each with 1 GB of allocated memory, without any issues (on my 4 GB Dell Studio XPS 16 laptop).

Sun VirtualBox is a popular, easy-to-use, free Virtualization software. I use it on 64-bit Windows Vista Ultimate (host OS) to virtualize Solaris10 and a few other Linux distributions. A frequent requirement is to share files and directories between the host OS and guest OSes. Sun VirtualBox makes this sharing easy with the "Shared Folders" feature. Given below are steps I followed to permanently share a directory on my host OS (Windows Vista) with Ubuntu 9.04 (guest OS) on Sun VirtualBox 3.04:

STEP 1: Configure the Shared Folder on the Sun VirtualBox GUI.

Select the Virtual Machine (Ubuntu 9.04) and click "Shared Folders" in the "Details" tab on the right pane. You will see the following window pop-up:

Click the “Add shared folder” icon, select a name for your shared folder, the path to the actual folder on your host OS and the access level for the folder.

I configured the following:

For Ubuntu 9.04 Guest OS:

Name = Ubuntu9.04

Path = E:\VirtualMachines\Ubuntu9.04

Access = Full

For Solaris 10 Guest OS:

Name = Solaris10

Path = E:\VirtualMachines\Solaris10

Access = Full

STEP 2: Mount the Shared Folder

For Ubuntu 9.04 Guest OS:

Temporary Mountpoint(disappears after rebooting Guest OS)

Start the Ubuntu 9.04 Virtual Machine, open a terminal window and enter the following command:

sudo mount -t vboxsf Ubuntu9.04 /whatever-you-want

Permanent Mountpoint (remains after rebooting Guest OS)

Start the Ubuntu 9.04 Virtual Machine, open a terminal window and add the following line to the /etc/fstab file:

Ubuntu9.04 /whatever-you-want vboxsf rw 0 0

Restart the Ubuntu 9.04 Guest OS.

For Solaris 10 Guest OS:

Temporary Mountpoint(disappears after rebooting Guest OS)

Start the Solaris 10 Virtual Machine, open a terminal window and enter the following command as the root user:

pfexec mount -F vboxsf Solaris10 /whatever-you-want

Permanent Mountpoint (remains after rebooting Guest OS)

Start the Solaris 10 Virtual Machine, open a terminal window and add the following line to the /etc/vfstab file: